A man who smothered his terminally-ill partner to death has revealed he has been left mentally scarred by his actions.

Author and journalist, Mark Sanderson, promised his lover Drew Morgan that he would help him to die after he was diagnosed with cancer.

He carried out his promise after the pain from skin cancer finally became too much for Drew to bear.

But in a moving interview for BBC's HARDtalk he said: "I think what I did was right for Drew but possibly wrong for me.

"If I'd have known quite what sort of psychological toll it would take on me I might not have done it."

He added: "I'm not sure if I did the right thing but I'm proud I could put somebody's wellbeing in front of my own."

Diagnosis

The couple met in September 1992 through a personal advert and within months had moved in together. For Mark these were the happiest months of his life.

But in October 1993, Drew went to the doctor after discovering a lump in his groin. He was diagnosed with skin cancer and within three months he was dead.

What I did was right for Drew but possibly wrong for me

Mark Sanderson

When Drew first asked Mark to promise he would help him die if the pain became too much, Mark admitted he did not take him seriously.

But after Drew came home from hospital for the final time to die he reminded Mark of the pledge.

That evening, Mark attempted to carry out his promise, but discovered Drew was not ready.

He explained: "He grabbed my wrists straight away as soon as I put the pillow over his head and pressed down....with a surprising strength which was really, really shocking and I stopped of course."

"I said 'I thought this is what you wanted', he said 'Yes it is-but not yet.' "

No doubt

A few days later Drew asked again. As he was unable to talk by now, Mark asked him to confirm 12 times by blinking that this was what he wanted.

Again, Mark took a pillow and this time smothered to death the man he loved.

In his memoir "Wrong Rooms" Mark writes honestly about what is like to cope when someone you love is suffering from cancer, or any terminal illness.

Mark revealed he is in absolutely "no doubt" that he did what Drew wanted.

He said: "He wanted to die. I wanted to help him. I would do whatever he wanted"

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Mark described the immediate sense of calm he felt afterwards. He said: "It was relief in a way. I didn't really feel anything at all. It still shocks me now in some ways that I went to sleep, I just went to sleep beside him."

In trying to come to terms with his loss he drank heavily, took drugs and attempted suicide.

"I attempted it (suicide) twice," he said "well once seriously but I always think that if you are going to commit suicide or you if you really want to kill yourself you will do it. So I'm ambivalent towards my suicide attempts."

Today he is still struggling to come to terms with what he did, although he does not believe that he committed murder.

"I don't consider that I did commit murder, I've never felt that I'm a killer, ever. The point about murder is that you're killing someone against their will."

Truth

Until he started writing "Wrong Rooms" he had not talked openly about what he did.

He is glad that the book has brought the truth out into the open but admitted it has not helped as much as he hoped.

"Whatever happens to me the story is out there and I think that's a good thing." He said.

With the release of the book Mark acknowledged that a police investigation and prosecution may be likely but he says that eight years on he is not the same person he was.

"I'm older and I think a little wiser." He said "I think know myself better now, what I'm capable of."

"I would certainly help Drew again but I would never get myself into those circumstances again. I never want to find myself in that situation again."